Boiler issue

My boiler system will start up just fine and heat the room as it should. Problem is that once the thermostat reads that the setpoint temperature and ambient are the same, it shuts the pilot light off. After ambient drops below the setpoint temperature the system won't light the pilot which obviously won't light the main burners. However, if I turn the boiler power off and then turn it back on(manually with a switch), it will fire right up and do exactly what its supposed to do. Any help would be great.

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Boiler issue

Quote:

Originally Posted by ajlboarder

My boiler system will start up just fine and heat the room as it should. Problem is that once the thermostat reads that the setpoint temperature and ambient are the same, it shuts the pilot light off. After ambient drops below the setpoint temperature the system won't light the pilot which obviously won't light the main burners. However, if I turn the boiler power off and then turn it back on(manually with a switch), it will fire right up and do exactly what its supposed to do. Any help would be great.

Edit: If helpful, its a Weil-McClain HE-3, Series 2

boiler is locking out for some reason. you are re-setting it when you turn the power on and off ,,,,,,

Boiler issue

Quote:

Originally Posted by ajlboarder

If any of these were the case, why does it work properly on start-up? Seems like some component based defect to me..

Because its a partial obstruction. And gets worse as the unit runs. then when the unit shuts off, the obstruction is still causing the problem. Its probably not satisfying the thermostat completely, and is locking near the end of the heat call.

Boiler issue

I have also noticed the following:
If thermostat is on and set to higher than ambient before boiler is turned on -> system works fine
If boiler is on before thermostat is set to "heat" -> system has the same problem (blower kicks on but wont light pilot)